Department of Analytical Chemistry, Helmholtz Centre for Environmental Research - UFZ, D-04317 Leipzig, Germany.
Department of Bioanalytical Ecotoxicology, Helmholtz Centre for Environmental Research - UFZ, D-04317 Leipzig, Germany.
Chem Res Toxicol. 2022 Feb 21;35(2):315-325. doi: 10.1021/acs.chemrestox.1c00371. Epub 2022 Jan 6.
Toxicokinetics (TK) of ionic compounds in the toxico-/pharmacological model zebrafish embryo () depend on absorption, distribution, metabolism, and elimination (ADME) processes. Previous research indicated involvement of transport proteins in the TK of the anionic pesticide bromoxynil in zebrafish embryos. We here explored the interaction of bromoxynil with the organic anion-transporting polypeptide zebrafish Oatp1d1. Mass spectrometry imaging revealed accumulation of bromoxynil in the gastrointestinal tract of zebrafish embryos, a tissue known to express Oatp1d1. In contrast to the Oatp1d1 reference substrate bromosulfophthalein (BSP), which is actively taken up by transfected HEK293 cells overexpressing zebrafish Oatp1d1, those cells accumulated less bromoxynil than empty vector-transfected control cells. This indicates cellular efflux of bromoxynil by Oatp1d1. This was also seen for diclofenac but not for carbamazepine, examined for comparison. Correspondingly, internal concentrations of bromoxynil and diclofenac in the zebrafish embryo were increased when coexposed with BSP, inhibiting the activities of various transporter proteins, including Oatp1d1. The effect of BSP on accumulation of bromoxynil and diclofenac was enhanced in further advanced embryo stages, indicating increased efflux activity in those stages. An action of Oatp1d1 as an efflux transporter of ionic environmental compounds in zebrafish embryos should be considered in future TK assessments.
离子化合物在毒理学/药理学斑马鱼胚胎模型中的毒代动力学（TK）取决于吸收、分布、代谢和消除（ADME）过程。先前的研究表明，转运蛋白参与了阴离子农药溴苯腈在斑马鱼胚胎中的 TK。在这里，我们研究了溴苯腈与有机阴离子转运蛋白斑马鱼 Oatp1d1 的相互作用。质谱成像显示溴苯腈在斑马鱼胚胎的胃肠道中积累，胃肠道是已知表达 Oatp1d1 的组织。与作为 Oatp1d1 参比底物的溴磺酞（BSP）不同，BSP 被过表达斑马鱼 Oatp1d1 的转染 HEK293 细胞主动摄取，而这些细胞积累的溴苯腈比空载体转染的对照细胞少。这表明 Oatp1d1 对溴苯腈具有细胞外排作用。用比较的方法，也观察到了双氯芬酸的情况，但卡马西平则没有。相应地，当与 BSP 共同暴露时，溴苯腈和双氯芬酸在斑马鱼胚胎中的内部浓度增加，抑制了包括 Oatp1d1 在内的各种转运蛋白的活性。BSP 对溴苯腈和双氯芬酸积累的影响在进一步发育的胚胎阶段增强，表明这些阶段的外排活性增加。在未来的 TK 评估中，应考虑 Oatp1d1 作为离子环境化合物在斑马鱼胚胎中的外排转运蛋白的作用。
